Another look at capping I-405 downtown

Over the past 15 years, Portland has added some memorable public spaces to its downtown core, including the Eastbank Esplanade in 2001, Jamison Square in 2002, Tanner Springs Park in 2005 and Director Park in 2009. But as one moves west from Director and the adjacent Pioneer Courthouse Square, there are relatively few greenspaces until one reaches Washington Park nearly a mile away. What if we were change that by capping a portion of the Interstate 405 trench as it bisects downtown and Goose Hollow?

That's the proposition of a new ideas competition sponsored by the Portland chapter of the American Institute of Architects called "Stitch," with its brief asking for "extraordinary creative proposals that will spark the imagination, open up a dialogue and offer innovative solutions to this urban problem."

The problem in question is the severing of downtown and areas west of the freeway, including Goose Hollow and the area around Providence Park, both of which are experiencing increased density via new developments. It's not that one literally can't cross I-405, for there are bridges across the span at Morrison, Yamhill, Taylor and Jefferson Streets. Yet there's little denying that the freeway's trench sucks life from what would otherwise be a vibrant urban cityscape. This isn't a matter of vilifying highways in urban areas; I drive my car on I-405, I-5 and I-84 fairly regularly. But how those freeways intersect and interact with the surrounding city has a huge impact on the surrounding areas. And it's not just a matter of aesthetics, for these urban design decisions have a direct and very substantial effect on the economics of place. Think of how much more valuable and likely to be prosperous a storefront facing a capped I-405 with a park would be compared to one overlooking a freeway trench.

"The opportunity to reclaim land that was consumed by the highway system provides a unique opportunity to address the need for more urban open space," the brief says, "but also to restitch two neighborhoods together."

This is not the first time the idea of capping I-405 has been floated. In the 1990s, then-mayor Vera Katz proposed capping 28 of the 36 blocks that were destroyed by the creation of the freeway in the 1950s. That was a much more ambitious proposal and would have cost many hundreds of millions.

The Stitch competition's site over I-405 (image courtesy AIA/Portland)

The AIA ideas competition starts with something smaller: a single 200-by-200-foot block, making the project equivalent in size to a regular city block. It's easy to see why this is a more manageable goal, both as a competition and potentially as a real project. But I'd have liked to see multiple blocks proposed, even if it's as little as two.

The Katz proposal also seemed to have in mind building buildings on a capped I-405, although one guesses they would have had to be limited in scale given the freeway running underneath a concrete cap. This competition eyes the I-405 cap as an opportunity to add greenspace, which is a nobler civic goal but would eliminate the incentive to create developable land. In an urban sense, though, it would be better for Portland to add greenspace over the freeway. This competition is really organized daydreaming anyway: why not imagine the best-case scenario?

I-405 is also part of a broader freeway loop with I-5, which crosses the river via the Marquam Bridge and hugs the Willamette's east bank for over a mile in the Central Eastside. If one really wanted to throw upen lots of new central-city land for development, the big move would be to tear down the Marquam and the east-side overpass and build a tunnel for I-5, thereby freeing up most all of the east side to reconnect with the river. Anyone who has spent time on the Vera Katz Eastbank Esplanade is accompanied by the almost deafening white noise of freeway traffic just a few feet away. The Esplanade is an urban bandage on an otherwise festering wound. Of course it would take a gigantic amount of money to do this, and frankly I've spent most of the past 15 years thinking it was all but impossible. Yet the Columbia Crossing would be no more expensive than building an I-5 tunnel, even though it would do little to improve traffic conditions and nothing to improve Portland or Vancouver's cityscapes. Vancouver, at least, has tied its own freeway-capping project, one over I-5, to the Columbia Crossing.

The city has many urban-planning priorities that would seem to trump an I-405 capping project, at least for now. Mayor Hales has often spoke of the development opportunity existing now on the east side of the Willamette near the new Tri-Met light rail and pedestrian bridge nearing completion. There are also alterations planned for I-5 at the Rose Quarter, where in late 2012 the Oregon Transportation Commission approved a plan that aims to alleviate I-5 traffic and remodel neighborhoods near the Rose Garden with new surface streets, a cap over the freeway with a possible park, and new bike- and pedestrian-friendly improvements. Given what an under-performing and untapped resource the Northeast Broadway is, with a new streetcar line and acres of developable high-density land on either side (at the Portland Public Schools Blanchard site and on the Rose Quarter site), it would make more sense for the city to direct its attention there.

Even so, the AIA "Stitch" competition (which accepts entries between March 17 and April 28, with winners announce May 16) is a worthwhile exercise, reminding us that while freeways are a necessary part of the city's transit mix, they don't have to cut concrete canyons through our city centers. They are not just eyesores but economic drains. But if automobile traffic were ever to drastically decrease, the Greetings From Portlandia blog has a fun idea: fill it with water and create our city's Venetian-style grand canal.

FYI....
On the second floor of the Portland Building in the south meeting room, there is an enormous site model of downtown Portland. There are also several models of architecture proposals for covering I-405. I think they were leftover from an old competition or design studio.

I own a condo overlooking the trench between Burnside and Couch. Just a polite request to cover that block first. My condo value would shoot up, I would sleep better at night, and I could give a sizeable tip to the designing architect.